The present invention relates to packaging apparatuses, and, in particular, to a machine used to cut a tube of flexible material within which an article is packaged.
A variety of differently configured apparatuses are currently utilized within the packaging industry. One well known packaging apparatus which is widely used, particularly in the cheese packaging industry, is a horizontal form, fill and seal type apparatus previously manufactured by Hayssen Manufacturing Company, which apparatus is similar in pertinent part to machines now being made by Hayssen, Inc. This apparatus forms a tube from a web of heat-sealable material, fills the horizontally moving tube with product spaced along the tube length, and then seals and severs the tube both in front of and behind the product as the tube enwrapped product is continuously moved along a rotary turret or die wheel.
In the past, tube severing has been accomplished with a roller that contacts a cutting element of the sealing unit that holds the tube. The roller is positioned proximate the bottom or underside of the rotary die wheel, and is mounted with its axle arranged parallel to the axis of rotation of the die wheel. As each sealing unit that clamps the tube between products continuously travels in a circular path with the die wheel on which it is carried, the roller engages the cutting element of that sealing unit so as to move the cutting element radially to sever the web between separate, successive products.
While useful, packaging apparatuses of this type are not without their shortcomings. Specifically, due at least in part to the fact that the web is severed only after it has been sealed by the sealing units carried by the rotating wheel, the web material has previously been of critical importance. The web material nearly required by this type of packaging apparatus is a three-ply lamination, such as a designer film product known as Curpolene(copyright) film available from Curwood, Inc. of New London, Wis.. Other web materials have not been well suited for use with such packaging apparatuses because such web materials are not reliably severed by the prior art roller since the heated web reaching the roller is simply too flexible for the roller-actuated cutting member. Consequently, while other web materials may provide properties which are acceptable from a sealing perspective, such materials have not been sufficiently severable within such packaging apparatuses and therefore have not been widely embraced by the industry.
Thus, it would be desirable to overcome this and other shortcomings of the prior art.
The present invention provides a machine for a packaging apparatus which applies an impulse load to cutting members installed in sealing dies that hold a tube of flexible packaging material. The impulse load on the cutting members is sufficient to achieve a quick and clean severing of the tube held within the sealing die, and allows tube materials to be used which normally are not suitable for use when the cutting members are roller actuated. The machine uses a striker element configured to move with the cutting member it is activating during the severing process, and as a result the machine does not interfere with the circular motion of the sealing dies as they are carried on a rotatable die wheel. The present invention can be used to cut tubes which have not been significantly heated during the tube sealing process, and consequently may be installed proximate the location at which the sealing dies first engage the tube wrapped article as the articles move through the packaging apparatus.
One advantage of the present invention is that a cutter activating machine may be provided which can be retrofit onto an existing packaging apparatus.
Another advantage of the present invention is that a cutter activating machine may be provided which is capable of severing different types of article enwrapping materials, thereby allowing packaging apparatuses to be used with different and possibly less expensive types of tube materials.
Still another advantage of the present invention is that a cutter activating machine may be provided which applies an impulse or short-acting load on a cutting member of a sealing unit carried by a continuously rotating wheel without requiring the sealing unit to be stopped or slowed during the application of that load.
Still another advantage of the present invention is that a cutter activating machine may be provided which can sever a tube held within a sealing die before that sealing die has heated the tube significantly during the sealing process.
Yet another advantage of the present invention is that a cutter activating machine may be provided which can sever heavier tubes or packaging materials, including resealable zipper portions of tubes.